The present invention relates to a hydro-energy converter and, more particularly but not exclusively, relates to a hydro-energy converter which is portable, able to float and capable of operating with a relatively low head which may be created by the converter itself.
The energy of running water has been exploited for very many years. However, traditional approaches have suffered disadvantages due to environmental factors, for example:
(a) damming a river floods land that would otherwise be available for use, alters the landscape, creates risk (such as of the dam failing), affects the local community that would have lived and worked on the flooded land, alters the character of the river, and prevents the free movement of fish;
(b) diverting a river affects the nature of the countryside and does not lend itself to use on a large scale; and
(c) permanent complete or partial blockage of a river for energy conversion is adversely affected by variations in flow.
It is therefore an object of the present invention to provide a hydro-energy converter which uses the potential energy of flowing water and which is environmentally acceptable.
According to the present invention there is provided a hydro-energy converter comprising a rotary member for converting energy of running water into rotary motion, means for securing the rotary member in a position such that water can run past the rotary member, and baffle means for creating a head of water upstream of the rotary member. The securing means may be configured for releasably securing the converter to a bed over which water is running.
A further rotary member may be provided with the further rotary member being located downstream of the first-mentioned rotary member.
A flow deflector may be provided at least in the region around the lower upstream quadrant of the rotary member. The flow deflector may be generally arcuate.
A plurality of cover plates may be provided over at least part of, and downstream of, the rotary member for deflecting water over the cover plates for concealing at least a part of the converter. At least the downstream cover plates may be pivotably mounted for minimising resistance to flow under flood conditions.
The baffle means may be provided immediately upstream of the rotary member. The baffle means may be pivotably mounted for minimising resistance to flow under flood conditions.
The rotary member may be connected to a buoyant member, for example by way of an arm which is pivotably connected to both the rotary member and the buoyant member. The buoyant member may be tethered to a base on which the rotary member is mounted. The tether length may be adjustable. Power generating means may be provided on the buoyant member and operatively connected to the rotary member.
The rotary member may be rotatable about an upright axis or an axis extending in the direction of the flow of water, such as a turbine. Alternatively, the rotatable member may be rotatable about an axis extending transverse to the direction of flow of water, such as a paddle wheel or the like.
The paddles of the wheel may be constructed to minimise resistance to the flow of oncoming water above the transverse axis of the wheel. For example, the paddles may be pivotably mounted in the region of the periphery of the wheel and rotatable at the free end thereof between a position bearing against a centre portion of the wheel in which the paddle presents maximal resistance to the oncoming flow of water and a trailing position in which the paddle presents minimal resistance to the oncoming flow of water.
The converter may include a passage permitting fish to swim past the rotary member.
Because the converter is anchored or tethered and not positioned in a permanent manner, it is a relatively straightforward matter to remove the converter from one location and to replace it at another location. That is, the converter is portable.
Thus the converter can rest, for example, on the bed of a river and at least a part of the converter can float as the level of the river rises. One or more converters can be tethered or anchored at various locations in a river for the purpose of generating electricity, pumping water or operating mechanisms or the like. To this end, the rotary member may be connected to an electrical generator, pump or the like and which may form part of the converter tethered or anchored relative to the running water or may be located remotely and connected to the rotary member by a suitable linkage, for example hydraulic or mechanical.
The nature of the converter is such that it need never totally block the natural flow of the river. There is no need for the converter to dominate the landscape, endanger fish or interfere adversely with recreational pursuits such as fishing or boating. The converter does not change the character of the river or create any harmful by-products.
Thus the converter of the present invention provides a means of generating clean power in an environmentally friendly manner.